Buried Object Detector

Abstract

A method and apparatus for locating buried objects comprising magnetic material and / or charge storage devices in a living animal. The apparatus can include a magnetic field generator (e.g., an electromagnetic field generator) configured to generate a magnetic field (e.g., an electromagnetic field). The apparatus can include a sensor configured to detect a change in the magnetic field and to generate a sensor signal indicative of the change in the magnetic field. The magnetic material and / or charge storage device of the buried object can cause a change in the magnetic field when the sensor is moved over the buried object. The apparatus can include a computer configured to use the sensor signal to detect the location of the buried object.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 327,566, filed April 5, 2022, the entire contents of which are incorporated by reference herein.

[0002] FIELD OF THEINVENTION

[0003] The present disclosure relates to an apparatus and method for detecting buried objects (also called implants) containing magnetic materials and / or charge storage devices in living animals. [Background technology]

[0003]

[0004] Background information

[0005] Implants, such as sensors, may be implanted within a living animal (e.g., a human). The implants may, for example, detect the presence or amount of an analyte (e.g., glucose or oxygen) in a medium (e.g., blood or interstitial fluid) within the living animal. Some implants may be relatively small (e.g., capsules 2 mm to 4 mm in diameter) and may be implanted in the subcutaneous tissue of the host. The implants may need to be located (e.g., for removal of the implant). Due to the small size of the implant, it may be difficult to locate and remove the implant from the subcutaneous tissue of the host. Summary of the Invention

[0004]

[0006] One aspect of the present invention can provide an apparatus for locating a buried object that includes a magnetic material. The apparatus can include a magnetic field generator, a sensor, and a computer. The magnetic field generator can be configured to generate a magnetic field. The sensor can be configured to detect a change in the magnetic field and to generate a sensor signal indicative of the change in the magnetic field. The magnetic material of the buried object can cause a change in the magnetic field when the sensor is moved over the buried object. The computer can be configured to use the sensor signal to detect the location of the buried object.

[0005]

[0007] In some embodiments, the magnetic field generator may include a cylindrical magnet. hi some embodiments, the cylindrical magnet may be hollow.

[0008] In some embodiments, the magnetic field generator can include one or more magnets. In some embodiments, the magnetic field generator can include two or more magnets. In some embodiments, the magnetic field generator can further include a housing configured to hold the two or more magnets. In some embodiments, the magnetic field generator can include four magnets. In some embodiments, the magnetic field generator can include six magnets. In some embodiments, the one or more magnets can include one or more permanent magnets. In some embodiments, the one or more magnets can include one or more electromagnets.

[0006]

[0009] In some aspects, the magnetic field generated by the magnetic field generator can be a substantially uniform magnetic field.

[0010] In some embodiments, the magnetic field can be substantially symmetric about a longitudinal axis at the center of the magnetic field generator. In some embodiments, the magnetic field can be non-uniform and / or asymmetric about a longitudinal axis at the center of the magnetic field generator. In some embodiments, the sensor can be positioned along or offset from the longitudinal axis at the center of the magnetic field generator.

[0007]

[0011] In one embodiment, the computer can be configured to determine the edge of the magnetic material of the implant based on the location of the bimodal peak in the change of the magnetic field during the movement of the sensor along the longitudinal axis of the implant. In one embodiment, the computer can be configured to determine the edge of the implant based on the determined edge of the magnetic material of the implant and one or more offsets between the edge of the implant and the edge of the magnetic material of the implant. In one embodiment, the computer can be configured to determine the depth of the implant based on the magnitude of the change of the magnetic field at the bimodal peak in the change of the magnetic field during the movement of the sensor along the longitudinal axis of the implant. In one embodiment, the computer can be configured to determine the orientation of the implant based on the difference between the magnitude of the change of the magnetic field at the bimodal peak in the change of the magnetic field during the movement of the sensor along the longitudinal axis of the implant.

[0008]

[0012] In some embodiments, the computer can be configured to calculate a derivative of the change in the magnetic field and use the calculated derivative to detect the location of the implant. In some embodiments, the derivative of the change in the magnetic field can be relative to time (during the movement of the sensor along the longitudinal axis of the implant). In some embodiments, the derivative of the change in the magnetic field can be relative to the position of the sensor (during the movement of the sensor along the longitudinal axis of the implant). In some embodiments, the computer can be configured to determine the edge of the magnetic material of the implant based on the location where the derivative of the change in the magnetic field during the movement of the sensor along the longitudinal axis of the implant is equal to zero. In some embodiments, the computer can be configured to determine the depth of the implant based on the magnitude of the change in the magnetic field at the location where the derivative of the change in the magnetic field during the movement of the sensor along the longitudinal axis of the implant is equal to zero. In some embodiments, the computer can be configured to determine the orientation of the implant based on the difference between the magnitudes of the change in the magnetic field at the location where the derivative of the change in the magnetic field during the movement of the sensor along the longitudinal axis of the implant is equal to zero. In some embodiments, the computer can be configured to determine the midline of the implant based on where the derivative of the change in the magnetic field during movement of the sensor across the longitudinal axis of the implant equals zero. In some embodiments, the derivative of the change in the magnetic field can be relative to time or position (as the sensor is moved across the longitudinal axis of the implant).

[0009]

[0013] In some embodiments, the computer can be further configured to use the one or more sensor signals to detect the orientation of the implant.

[0014] In some aspects, the device can further include a display, and the computer can be configured to cause the display to display an indication of the detected location of the buried object. In some aspects, the display can be positioned above the sensor. In some aspects, the indication of the detected location of the buried object can include an image of the buried object, and a location of the image of the buried object on a screen of the display relative to a point on the screen of the display can correspond to the detected location of the buried object relative to the sensor. In some aspects, the image of the buried object can have an orientation that corresponds to the detected orientation of the buried object.

[0010]

[0015] In some aspects, the device can further include an incision marking tool configured to identify an incision location for removing implants.

[0016] In some embodiments, the diameter of the magnetic field generator may be equal to the length of the implant.

[0011]

[0017] In some aspects, the device can further include a position detector configured to generate a location signal indicative of a location of the sensor on the skin surface. In some aspects, the position detector can include a motion detector configured to detect movement of the sensor and to generate a motion signal indicative of the detected movement of the sensor, the location signal including the motion signal. In some aspects, the computer can be configured to use the sensor signal and the location signal to generate a map of the sensor signal at different locations of the sensor on the skin surface.

[0012]

[0018] Another aspect of the invention can provide a method of locating a buried object including a magnetic material. The method can include using a magnetic field generator to generate a magnetic field. The method can include using a sensor to detect a change in the magnetic field and to generate a sensor signal indicative of the change in the magnetic field. The magnetic material of the buried object can cause the change in the magnetic field when the sensor is moved over the buried object. The method can include using a computer to detect a location of the buried object based on the sensor signal.

[0013]

[0019] In one aspect, detecting the location of the implant can include determining an edge of the magnetic material of the implant based on the location of a bimodal peak in the change in magnetic field during movement of the sensor along the longitudinal axis of the implant.

[0014]

[0020] Yet another aspect of the invention may provide a method of locating an implant including a magnetic material. The method may include moving an apparatus including a magnetic field generator and a sensor across a longitudinal axis of the implant. The magnetic material of the implant may cause a change in a magnetic field generated by the magnetic field generator when the apparatus is moved across the longitudinal axis of the implant, and the sensor may detect the change in the magnetic field. The method may include determining a midline of the implant based on a location of a maximum change in the magnetic field when the apparatus is moved across the longitudinal axis of the implant. The method may include moving the apparatus along the determined midline of the implant. The method may include determining an edge of the magnetic material of the implant based on a location of a bimodal peak in the change in the magnetic field when the apparatus is moved along the determined midline of the implant.

[0015]

[0021] In some embodiments, the method can further include using an incision marking tool of the device to mark an incision location for implant removal.

[0022] Yet another aspect of the invention can provide an apparatus for locating a buried object including a charge storage device. The apparatus can include an electromagnetic field generator, a sensor, and a computer. The electromagnetic field generator can be configured to generate an electromagnetic field. The sensor can be configured to detect a change in the electromagnetic field and to generate a sensor signal indicative of the change in the electromagnetic field. The charge storage device of the buried object can cause a change in the electromagnetic field when the sensor is moved over the buried object. The computer can be configured to use the sensor signal to detect the location of the buried object.

[0016]

[0023] Yet another aspect of the invention can provide a method of locating a buried object including a charge storage device. The method can include using an electromagnetic field generator to generate an electromagnetic field. The method can include using a sensor to detect a change in the electromagnetic field and to generate a sensor signal indicative of the change in the electromagnetic field. The charge storage device of the buried object can cause a change in the electromagnetic field when the sensor is moved over the buried object. The method can use a computer to detect a location of the buried object based on the sensor signal.

[0017]

[0024] Yet another aspect of the invention may provide a method of locating a buried object including a charge storage device. The method may include moving an apparatus including an electromagnetic field generator and a sensor across a longitudinal axis of the buried object. The charge storage device of the buried object may cause a change in an electromagnetic field generated by the electromagnetic field generator when the apparatus is moved across the longitudinal axis of the buried object, and the sensor may detect the change in the electromagnetic field. The method may include determining a midline of the buried object based on a location of a maximum change in the electromagnetic field when the apparatus is moved across the longitudinal axis of the buried object. The method may include moving the apparatus along the determined midline of the buried object. The method may include determining an edge of the charge storage device of the buried object based on a location of a bimodal peak in the change in the electromagnetic field when the apparatus is moved along the determined midline of the buried object.

[0018]

[0025] These and other embodiments encompassed by the systems and methods are described in the detailed description of the invention below.

[0026] Various non-limiting embodiments of the present invention are illustrated in the accompanying drawings, which are incorporated in and form a part of this specification, where like reference numbers indicate identical or functionally similar elements. [Brief description of the drawings]

[0019] [Figure 1]

[0027] 1 is a block diagram illustrating a non-limiting example of a buried object and buried object detector embodying aspects of the present invention; [Figure 2A]

[0028] 1 is a cross-sectional side view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention; [Figure 2B]

[0029] 1 is a cross-sectional top view of a non-limiting example of a buried object detector embodying aspects of the present invention. [Figure 2C]

[0030] 1 is a two-dimensional contour plot slice in the XY plane illustrating the magnitude of the magnetic field generated by a non-limiting example of a hollow cylindrical magnetic field generator, embodying aspects of the present invention. [Figure 2D] 1 is a two-dimensional contour plot slice in the ZY plane illustrating the magnitude of the magnetic field generated by a non-limiting example of a hollow cylindrical magnetic field generator, embodying aspects of the present invention. [Figure 2E]

[0031] 1 is a cross-sectional top view of a non-limiting example of a buried object detector embodying aspects of the present invention. [Figure 2F]

[0032] 1 is a two-dimensional contour plot slice in the XY plane illustrating the magnitude and vectors of the magnetic field generated by a non-limiting example of a field generator including six magnets, embodying aspects of the present invention. [Figure 2G] 1 is a two-dimensional contour plot slice in the ZY plane showing the magnitude and vectors of the magnetic field generated by a non-limiting example of a field generator including six magnets, embodying aspects of the present invention. [Figure 2H]

[0033] FIG. 2 illustrates a two-dimensional contour plot slice in the XY plane showing the magnitude and vectors of the magnetic field generated by a non-limiting example of a magnetic field generator including four magnets, embodying aspects of the present invention. [Figure 2I] FIG. 2 is a two-dimensional contour plot slice in the ZY plane showing the magnitude and vectors of the magnetic field generated by a non-limiting example of a magnetic field generator including four magnets, embodying aspects of the present invention. [Figure 3A]

[0034] 1 is a cross-sectional side view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention; [Figure 3B]

[0035] 1 is a two-dimensional contour plot slice in the XY plane illustrating the magnitude and vectors of the magnetic field generated by a non-limiting example of a cylindrical magnetic field generator, embodying aspects of the present invention. [Figure 3C] 1 is a two-dimensional contour plot slice in the ZY plane illustrating the magnitude and vectors of the magnetic field generated by a non-limiting example of a cylindrical magnetic field generator, embodying aspects of the present invention. [Figure 4A]

[0036] FIG. 1 illustrates a non-limiting example of a magnetometer including a sensor for a buried object detector embodying aspects of the present invention. [Figure 4B] FIG. 1 illustrates a non-limiting example of a magnetometer including a sensor for a buried object detector embodying aspects of the present invention. [Figure 5A]

[0037] 1 is a perspective view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention; FIG. [Figure 5B] 1 is a perspective view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention; FIG. [Figure 5C]

[0038] FIG. 1 is a perspective transparent view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention. [Figure 5D]

[0039] 1 is a perspective view of a non-limiting example of a buried object and a magnetic field generator and sensor of a buried object detector embodying aspects of the present invention; FIG. [Figure 5E] 1 is a top view of a non-limiting example of a buried object and a magnetic field generator and sensor of a buried object detector embodying aspects of the present invention; [Figure 5F]

[0040] FIG. 1 is a perspective transparent view of a non-limiting example of a buried object and a magnetic field generator and sensor of a buried object detector embodying aspects of the present invention. [Figure 6]

[0041] FIG. 2 is a block diagram illustrating a non-limiting example of a buried object detector computer embodying aspects of the present invention. [Figure 7A]

[0042] 1 is a cross-sectional side view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention. [Figure 7B]

[0043] 1A-1C are diagrams illustrating non-limiting examples of display screens of a user interface of a buried object detector embodying aspects of the present invention. [Figure 7C] 1A-1C are diagrams illustrating non-limiting examples of display screens of a user interface of a buried object detector embodying aspects of the present invention. [Figure 7D] 1A-1C are diagrams illustrating non-limiting examples of display screens of a user interface of a buried object detector embodying aspects of the present invention. [Figure 7E] 1A-1C are diagrams illustrating non-limiting examples of display screens of a user interface of a buried object detector embodying aspects of the present invention. [Figure 7F] 1A-1C are diagrams illustrating non-limiting examples of display screens of a user interface of a buried object detector embodying aspects of the present invention. [Figure 8A]

[0044] 1 is a perspective view of a non-limiting example of an implant embodying aspects of the present invention; FIG. [Figure 8B] 1 is a perspective view of a non-limiting example of an implant embodying aspects of the present invention; FIG. [Figure 9A]

[0045] 13A-13C are diagrams illustrating movement of an implant locator transverse to the longitudinal axis of an implant that is not inclined relative to the skin surface, embodying aspects of the present invention. [Figure 9B] FIG. 13 illustrates the magnitude of change applied to the magnetic field during the above movement, embodying aspects of the present invention. [Figure 9C]

[0046] 11A-11C show a diagram illustrating movement of an implant detector along the longitudinal axis of an implant that is not tilted relative to the skin surface, embodying aspects of the present invention. [Figure 9D]FIG. 13 illustrates the magnitude of change applied to the magnetic field during the above movement, embodying aspects of the present invention. [Figure 9E]

[0047] FIG. 1 shows identified implant margins and marked incision locations embodying aspects of the present invention. [Figure 10A]

[0048] 1A-1C are diagrams illustrating the movement of a buried object detector across the longitudinal axis of a downwardly tilted buried object, embodying aspects of the present invention. [Figure 10B] FIG. 13 illustrates the magnitude of change applied to the magnetic field during said motion, embodying aspects of the present invention. [Figure 10C]

[0049] 1A-1C are diagrams illustrating the movement of a buried object detector across the longitudinal axis of a downwardly tilted buried object, embodying aspects of the present invention. [Figure 10D] FIG. 13 illustrates the magnitude of change applied to the magnetic field during said motion, embodying aspects of the present invention. [Figure 10E]

[0050] FIG. 1 shows implant margins identified and incision locations marked, embodying aspects of the present invention. [Figure 11A]

[0051] 1A-1C are diagrams illustrating movement of a buried object detector transverse to the longitudinal axis of the buried object, embodying aspects of the present invention. [Figure 11B] 11A-11C are diagrams illustrating the magnitude of change applied to the magnetic field during said movement for different distances between the sensor and the implant, embodying aspects of the present invention. [Figure 12A]

[0052] 1A-1C are diagrams illustrating movement of a buried object detector along the longitudinal axis of a buried object, embodying aspects of the present invention. [Figure 12B] 11A-11C show diagrams illustrating the magnitude of change applied to the magnetic field during said movement for different distances between the sensor and the implant, embodying aspects of the present invention. [Figure 13A]

[0053] 1A-1C are diagrams illustrating movement of a buried object detector in an oblique direction relative to the longitudinal axis of the buried object, embodying aspects of the present invention. [Figure 13B]11A-11C show the magnitude of change applied to the magnetic field during said movement, embodying aspects of the present invention. [Figure 13C]

[0054] 1A is a diagram showing the X-component of the magnetic field change when a buried object detector is moved in a diagonal direction relative to the longitudinal axis of the buried object, embodying an embodiment of the present invention. FIG. [Figure 13D] 1A illustrates the Y component of the magnetic field change when a buried object detector is moved in a diagonal direction relative to the longitudinal axis of the buried object, embodying an embodiment of the present invention. [Figure 13E] 1A-1C are diagrams illustrating the Z component of the magnetic field change when a buried object detector is moved in a diagonal direction relative to the longitudinal axis of the buried object, embodying an embodiment of the present invention. [Figure 14A]

[0055] FIG. 1 illustrates an out-of-plane twisted implant embodying aspects of the present invention. [Figure 14B] FIG. 14B illustrates changes applied to the magnetic field during movement of the buried object detector transverse to the longitudinal axis of the buried object detector, embodying an embodiment of the present invention. [Figure 14C] FIG. 14A illustrates changes to the magnetic field during movement of the implant locator along the longitudinal axis of the implant, embodying an embodiment of the present invention. [Figure 15]

[0056] 15A illustrates the movement of an implant locator to identify implant orientation, embodying an embodiment of the present invention; FIG 15B illustrates the movement of an implant locator along the implant's longitudinal axis, embodying an embodiment of the present invention; and FIG 15C illustrates the identified implant margins and marked incision location, embodying an embodiment of the present invention. [Figure 16]

[0057] Fig. 16A is a diagram showing the approximate location of the implant embodying an embodiment of the present invention, Fig. 16B is a diagram showing marks indicating the course of movement of the implant detector in Fig. 16A embodying an embodiment of the present invention, Fig. 16C is a diagram showing the identification of the implant margin and incision coordinates in Fig. 16A embodying an embodiment of the present invention. [Figure 17]

[0058] 1 is a flow chart illustrating a non-limiting example of a process for exploring implants containing magnetic material, embodying aspects of the present invention. [Figure 18]

[0059] 1 is a flow chart illustrating a non-limiting example of a process for exploring implants containing magnetic material, embodying aspects of the present invention. [Figure 19]

[0060] FIG. 1 is a side view of a non-limiting example of an implant embodying aspects of the present invention. [Figure 20]

[0061] 1 is a block diagram illustrating a non-limiting example of a buried object and buried object detector embodying aspects of the present invention. [Figure 21A]

[0062] 1 is a cross-sectional side view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention. [Figure 21B]

[0063] 1 is a cross-sectional top view of a non-limiting example of a buried object detector embodying the present invention; [Figure 21C]

[0064] 1 is a perspective view of a non-limiting example of a buried object and buried object detector embodying aspects of the present invention; FIG. [Figure 22]

[0065] 1 is a flow chart illustrating a non-limiting example of a process for searching for an implant containing a charge storage device, embodying aspects of the present invention. [Diagram 23]

[0066] 1 is a flow chart illustrating a non-limiting example of a process for searching for an implant containing a charge storage device, embodying aspects of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020]

[0067] FIG 1 is a block diagram illustrating an implant 100 and an implant locator 101 embodying an embodiment of the present invention. In one embodiment, the implant locator 101 can be for locating an implant 100 that may be embedded in tissue below the surface of the skin of a living animal. In one embodiment, as shown in FIG 1, the implant 100 can include a magnetic material 124 (e.g., a magnetic core). In one embodiment, the magnetic material 124 can include, for example, but not limited to, a ferromagnetic material (e.g., iron) or a ferrimagnetic material (e.g., ferrite).

[0021]

[0068] In one embodiment, the buried object detector 101 can include a magnetic field generator 103, a sensor 105, a computer 106, a battery 117, a wireless communication integrated circuit (IC) 119, a connector 121 and a connector IC 123, a charger IC 125, a user interface 127, and / or a position detector 137. In one embodiment, the user interface 127 of the buried object detector 101 can include a display 129 (e.g., an optical display, such as, for example, a light emitting diode (LED) display), a speaker 131, a vibration motor 133, and / or a user input 135.

[0022]

[0069] In some embodiments, the magnetic field generator 103 can be configured to generate a magnetic field. In some embodiments, the sensor 105 can be configured to detect a change in the magnetic field and generate a sensor signal indicative of the change in the magnetic field. In some embodiments, the magnetic material 124 of the implant 100 can cause a change in the magnetic field when the sensor 105 is moved over the implant 100. In some embodiments, the computer 106 can be configured to use the sensor signal to detect the location of the implant 100.

[0023]

[0070] In certain embodiments, as shown in Figures 2A, 2B, 2E, and 3A, the magnetic field generator 103 can include one or more magnets 109. In certain embodiments, the one or more magnets 109 can be, for example, but not limited to, permanent magnets and / or electromagnets (e.g., a coil of wire wound around a magnetic core made of a ferromagnetic or ferrimagnetic material). In certain embodiments, as shown in Figures 5A-5C, the magnetic field generator 103 can include a housing 107, which can be configured to hold the one or more magnets 109. However, the housing 107 is not required, and in certain alternative embodiments (e.g., some embodiments in which the magnetic field generator 103 consists of only a single magnet 109), the magnetic field generator 103 does not include a housing 107.

[0024]

[0071] In one embodiment, as shown in Figures 2A, 2B, and 2E, the sensor 105 can be located on the longitudinal axis at the center of the magnetic field generator 103. However, this is not required, and in some other embodiments, the sensor 105 is not located on the longitudinal axis at the center of the magnetic field generator 103. For example, as shown in Figure 3A, the sensor 105 may be located adjacent to the magnet 109 of the magnetic field generator 103 (rather than at the center of the magnet or magnets 109 of the magnetic field generator 103).

[0025]

[0072] In some embodiments, the magnetic field generator 103 can include a hollow cylindrical magnet 109, as shown in Figure 2B. In some other embodiments, the magnetic field generator 103 can include two or more magnets 109 (e.g., four or six magnets), as shown in Figure 2E. In some other embodiments, the magnetic field generator 103 can include a solid cylindrical magnet 109, as shown in Figure 3A.

[0026]

[0073] In an embodiment, the one or more magnets 109 of the magnetic field generator 103 can generate a substantially uniform magnetic field. In an embodiment, the hollow cylindrical magnet 109 of the magnetic field generator 103 shown in FIG. 2B can generate a magnetic field having a magnitude shown in the two-dimensional contour slices of FIG. 2C and FIG. 2D. In an embodiment, the six magnets 109 of the magnetic field generator 103 shown in FIG. 2E can generate a magnetic field having a magnitude shown in the two-dimensional contour slices of FIG. 2F and FIG. 2G. In an embodiment, the magnetic field generator 103 can include four magnets 109, which can generate a magnetic field having a magnitude shown in the two-dimensional contour slices of FIG. 2H and FIG. 2I. In an embodiment, the solid cylindrical magnet 109 of the magnetic field generator 103 shown in FIG. 3A can generate a magnetic field having a magnitude shown in the two-dimensional contour slices of FIG. 3B and FIG. 3C. In some embodiments, the magnetic field generated by the one or more magnets 109 of the magnetic field generator 103 can be substantially symmetric about a longitudinal axis at the center of the magnetic field generator 103, as shown in Figures 2C, 2D, 2F-2I, 3B, and 3C. However, this is not required, and in some other embodiments, the magnetic field may have a different profile (e.g., the magnetic field may be non-uniform and / or asymmetric about the longitudinal axis at the center of the magnetic field generator). In some embodiments, the sensor 105 can be positioned on the longitudinal axis at the center of the magnetic field generator 103, as shown in Figures 2A, 2B, and 2E.

[0027]

[0074] In an embodiment, the sensor 105 can be a magnetic field sensor. In an embodiment, the sensor 105 can be a tunneling magnetoresistance (TMR) magnetic field sensor (e.g., a TMR full-bridge magnetic field sensor) or a Hall sensor (e.g., a high-field Hall sensor). In an embodiment, the sensor 105 can be part of a magnetometer 400 (e.g., an axial low-field magnetometer), as shown in FIGS. 4A and 4B. In an embodiment, the magnetometer 400 can include the sensor 105 and a probe 402 (e.g., a rigid probe), a cable 404 (e.g., a flexible cable), data acquisition electronics 406, and / or a connector 408 (e.g., a USB connector). In an embodiment, the connector 408 of the magnetometer 400 can be connected to the computer 106 of the buried object detector 101.

[0028]

[0075] In one embodiment, as shown in FIGS. 5A-5F, the buried object detector 101 can include a magnetic field generator 103 and a sensor 105. In one embodiment, the sensor 105 can be positioned on the longitudinal axis at the center of the magnetic field generator 103. In one embodiment, the magnetic field generator 103 can include a housing 107. In one embodiment, the housing 107 can include a housing body 115 (e.g., a polymer body). In one embodiment, as shown in FIGS. 5C-5F, the magnetic field generator 103 can include one or more magnets 109. In one embodiment, the housing 107 can be configured to accommodate one or more magnets 109. In one embodiment, as shown in FIGS. 5C-5F, the magnetic field generator 103 can include six magnets 109. However, in some other embodiments, the magnetic field generator 103 can include a different number of magnets 109 (e.g., 10, 9, 8, 7, 5, 4, 3, or 2 magnets, or a single magnet such as a hollow cylindrical magnet). In some embodiments, as shown in Figure 5E, the diameter or width of the magnetic field generator 103 can be equal to the length of the implant 100. However, this is not required, and in some other embodiments, the magnetic field generator 103 may have a different size (e.g., a diameter or width that is smaller or larger than the length of the implant 100).

[0029]

[0076] In one embodiment, as shown in FIGS. 5A-5C, the buried object locator 101 can include a handle 111. In one embodiment, as shown in FIGS. 5A-5C, the buried object locator 101 can include an incision marking tool 113. In one embodiment, the incision marking tool 113 can be configured such that a user can use the incision marking tool 113 to mark a suitable location on the skin surface 154 for an incision that will enable removal of the buried object 100. In one embodiment, a user can use the incision marking tool 113 to mark an incision location once the buried object locator 101 is placed on the buried object 100. In one embodiment, the incision marking tool 113 can be configured to mark the skin surface 154 above a determined edge of the buried object 100, a determined center of the buried object 100, a determined edge of the magnetic material 124, or a determined center of the magnetic material 124. In another embodiment, the incision marking tool 113 can be configured to mark the skin surface 154 above a location offset from the determined edge of the implant 100, the determined center of the implant 100, the determined edge of the magnetic material 124, and / or the determined center of the magnetic material 124. In another embodiment, the incision marking tool 113 can be configured to mark the skin surface at a longitudinal axis at the center of the magnetic field generator 103.

[0030]

[0077] In an aspect in which the buried object detector 101 includes a connector 121, the connector 121 can be, for example, but not limited to, a micro universal serial bus (USB) connector. In an aspect, the connector 121 can be configured to allow for a wired connection to an external device, such as a personal computer or a display device. In an aspect, the buried object detector 101 can exchange data with the external device via the connector 121 and / or can receive power via the connector 121. In an embodiment, the connector IC 123 can be, for example, but not limited to, a USB-IC that can control the transmission and reception of data via the connector 121.

[0031]

[0078] In an embodiment in which buried object detector 101 includes battery 117, battery 117 can provide operating power to buried object detector 101. In an embodiment, battery 117 can be a rechargeable battery. In an embodiment, battery 117 can be, for example but not limited to, a lithium-polymer battery. In an embodiment, battery 117 can have a short charging period and / or a small size. In an embodiment in which display device 105 includes charger IC 125, charger IC 125 can receive power via connector 121 to charge battery 117.

[0032]

[0079] In an aspect in which the buried object detector 101 includes a wireless communication IC 119, the wireless communication IC 119 can enable wireless communication with one or more external devices, such as, for example, one or more personal computers and / or one or more other display devices (e.g., a smartphone or tablet running an application). In an aspect, the wireless communication IC 119 can employ one or more wireless communication standards to wirelessly transmit data. The wireless communication standard employed can be an appropriate wireless communication standard, such as the IEEE 802.11 standard, the ANT standard, the Bluetooth standard, or the Bluetooth Low Energy (BLE) standard (e.g., BLE 4.0). In an aspect, the wireless communication IC 119 can include an antenna (e.g., a Bluetooth antenna, a Wi-Fi antenna, and / or one or more cellular antennas). In an aspect, the antenna of the wireless communication IC 119 can be completely accommodated within the housing of the buried object detector 101 (e.g., the housing 107). However, this is not required, and in another embodiment, all or a portion of the antenna of the wireless communication IC 119 can be outside the housing of the buried object detector 101.

[0033]

[0080] In some embodiments in which the object detector 101 includes a position detector 137, the position detector 137 can be configured to generate a location signal indicative of the location of the sensor on the skin surface 154. In some embodiments, the position detector 137 can include a motion detector configured, for example but not limited to, to detect movement of the sensor 105 (and / or the object detector 101) relative to the skin surface 154 and to generate a motion signal indicative of the detected movement of the sensor 105, where the location signal can include the motion signal. In some embodiments, the motion detector can include a mechanical motion detector (e.g., utilizing the movement of a ball within a mechanical motion detector) and / or an optical motion detector (e.g., using light to detect movement of the sensor 105).

[0034]

[0081] In some embodiments in which buried object detector 101 includes a user interface 127, user interface 127 may include one or more of a display 129 and a user input 135. In some embodiments, display 129 may include a liquid crystal display (LCD) and / or a light emitting diode (LED) display. In some embodiments, user input 135 may include one or more buttons, a keyboard, a keypad, and / or a touch screen. In some embodiments, user interface 127 may include one or more of a speaker 131 (e.g., a beeper) and a vibration motor 133 that may be activated, for example, when a condition is met (e.g., detection of an edge of buried object 100 and / or detection of a midline of buried object 100).

[0035]

[0082] In some embodiments in which the buried object detector 101 includes a computer 106, the computer 106 can control the overall operation of the buried object detector 101. For example, the buried object detector 101 can control the wireless communication IC 119, the controller IC 123, the charger IC 125, the position detector 137, the magnetic field generator 103, the sensor 105, and / or the user interface 127. In some embodiments, the computer 106 can receive and / or process data from the sensor 105, the position detector 137, and / or the user input 135 of the user interface 127. For example, in some embodiments, the computer 106 can be configured to use a sensor signal generated by the sensor 105 to detect the location of the buried object 100. In some embodiments, the computer 106 can be configured to use the sensor signal generated by the sensor 105 and the location signal generated by the position detector 137 to generate a map of the sensor signal at different locations of the sensor 105 on the skin surface 154. In some embodiments, the computer 106 can additionally or alternatively control the display 129, the speaker 131, and / or the vibration motor 135 to provide information regarding the detected location of the buried object 100. For example, in some embodiments, the computer 106 can cause the display 129 to display a notification (e.g., one or more light displays generated by one or more LEDs), the speaker 131 to beep, and / or the vibration motor 135 to vibrate when the computer 106 detects the edge of the buried object 100 and / or the midline of the buried object 100. In some embodiments, the computer 106 can additionally or alternatively be configured to cause the display 129 to display an indication of the detected location of the buried object 100 on a screen.

[0036]

[0083] 6 is a block diagram of the computer 106 of the buried object detector 101 according to an embodiment. In an embodiment, the computer 106 can be adapted to perform any of the methods, processes, or steps disclosed herein. As shown in FIG. 6, the computer 106 can include a processing circuit (PC) 302, which can include one or more processors (P) 355 (e.g., one or more general-purpose microprocessors and / or one or more other processors, such as application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), etc.).

[0037]

[0084] In an aspect, as shown in FIG. 6, the computer 106 may include one or more storage units (also referred to as “data storage systems”) 308, which may be co-located or geographically distributed and may include one or more non-volatile storage devices and / or one or more volatile storage devices. In an aspect where the PC 302 includes a programmable processor, the one or more storage units may include a computer program product (CPP) 341. In an aspect, the CPP 341 may include a computer readable medium (CRM) 342 that stores a computer program (CP) 343 that includes computer readable instructions (CRI) 344. In an aspect, the CRM 342 may be a non-transitory computer readable medium, such as a magnetic medium (e.g., hard disk), an optical medium, a memory device (e.g., random access memory, flash memory), or the like. In an aspect, the CRI 344 of the computer program 343 is such that when executed by the PC 302, the CRI 344 can cause the computer 106 to perform the steps described herein (e.g., steps described herein with reference to a flow chart). In other aspects, computer 106 can be adapted to perform the steps described herein without the need for code, i.e., PC 302 may consist only of one or more ASICs, and thus the mechanisms of the aspects described herein can be implemented in hardware and / or software.

[0038]

[0085] In one embodiment, as shown in FIGURE 7A, the display 129 of the user interface 127 of the buried object detector 101 can be positioned above the sensor 105. In one embodiment, the magnetic field generator 103 can be configured to hold the display 129 in place at the top of the buried object detector 101. In one embodiment, as shown in FIGURE 7A, the housing 107 of the magnetic field generator 103 can be configured to house the one or more magnets 109, the computer 106, and / or the display 129 of the magnetic field generator 103. However, this is not required, and in some alternative embodiments, the display 129 can be positioned above the magnetic field generator 103.

[0039]

[0086] In some embodiments, as shown in Figures 7B-7F, the display 129 of the user interface 127 can include a display screen 702. In some embodiments (e.g., some embodiments in which the display 129 is disposed above the sensor 105 and the computer 106 is configured to cause the display 129 to display a display of the detected location of the buried object 100), the display of the detected location of the buried object 100 can include a buried object image 704, and the location of the buried object image 704 on the screen 702 of the display 129 relative to a point on the screen 702 of the display 129 (e.g., its center) can correspond to the detected location of the buried object 100 relative to the sensor 105. In some embodiments, as shown in Figures 7B-7E, the buried object image 704 can have an orientation that corresponds to the orientation of the buried object 100 detected by the computer 106 using the sensor signal generated by the sensor 105.

[0040]

[0087] In some embodiments, depending on the location of the buried object 100 relative to the sensor 105, as shown in FIG. 7C, the buried object image 704 may be a partial buried object image. In some embodiments, as shown in FIGS. 7B-7F, a mark 706 may identify a point on the screen 702 that corresponds to the location of the sensor 105. In some embodiments (e.g., some embodiments in which the screen 702 of the display 129 is larger than and / or extends beyond the field generator 103), the computer 106 may cause the display 129 to display a field generator image 708 that indicates the location of the perimeter of the field generator 103, as shown in FIG. 7E. In some embodiments, the location of the buried object image 704 relative to the field generator image 708 may correspond to the detected location of the buried object 100 relative to the location of the field generator 103. In one embodiment, as shown in FIG. 7F, the computer 106 can cause the display 129 to display a target area 710, and the implant detector 101 can be appropriately positioned over the implant 100 so that an incision location can be marked (e.g., using the incision marking tool 113) once the implant image 704 is detected within the target area 710.

[0041]

[0088] 8A and 8B show non-limiting examples of implants 100 that can be detected by implant detector 101. In one embodiment, implant 100 can be a small, fully subcutaneously implantable sensor that measures the amount or concentration of an analyte (e.g., glucose) in a medium (e.g., interstitial fluid) of a living animal (e.g., a human body). In another embodiment, implant 100 is not a sensor, but instead can be a different type of implantable device, such as, but not limited to, a tag, an insulin pump, a pacemaker, or an electrical / thermal therapy device.

[0042]

[0089] 8A, the implant 100 may be implanted in tissue 150 (e.g., subcutaneous tissue) of a living animal, where the implant 100 can rest in a pocket 152 in the tissue 150 below a skin surface 154, which can surround the implant 100. In some embodiments, the pocket 152 can be formed by a tissue dissector tool prior to implantation of the implant 100 or by the implantation process.

[0043]

[0090] In one embodiment, as shown in FIG. 8A, an implant 100 can include a housing 102 and one or more analyte indicators 104 coated, coated, adhered, embedded or grown on or in at least a portion of an exterior surface of the housing 102. In one embodiment, the one or more analyte indicators 104 (e.g., a polymer graft or hydrogel) of the implant 100 can include one or more indicator molecules (e.g., fluorescent indicator molecules). In one embodiment, the indicator molecules can produce (e.g., exhibit) one or more detectable properties (e.g., optical properties) that vary depending on the amount or concentration of analyte in the vicinity of the analyte indicator 104. In one embodiment, the indicator molecules can emit an amount of light emission (e.g., fluorescence) that varies depending on the amount or concentration of analyte in the vicinity of the analyte indicator 104.

[0044]

[0091] In certain aspects, implant 100 can include a substrate 110 (e.g., a printed circuit board (PCB) or a flexible PCB), one or more light sources 111 mounted on or fabricated within substrate 110, and one or more photodetectors 112, 114, and 116 (e.g., photodiodes, phototransistors, photoresistors, or other light sensitive elements) mounted on or fabricated within substrate 110. In certain embodiments, light source 111 can be configured to emit excitation light over a range of excitation wavelengths that interact with one or more indicator molecules in analyte indicator 104. In certain aspects, one or more of photodetectors 112, 114, and 116 can output a signal indicative of the amount of light received by the photodetector. In certain examples, the signal output by one or more of photodetectors 112, 114, and 116 can indicate the amount or concentration of analyte in a medium proximate analyte indicator 104.

[0045]

[0092] In an embodiment, as shown in FIGS. 8A and 8B, the implant 100 can include an inductor 120, which can be, for example, a ferrite-based micro-antenna. In an embodiment, the inductor 120 can include a conductor 122 in the form of a coil and a magnetic material 124 in the form of a magnetic core 124. In an embodiment, the magnetic core 124 can be, for example, but not limited to, a ferrite core. In an embodiment, the inductor 120 can be connected to the circuitry (e.g., an application specific integrated circuit (ASIC)) of the implantable device 100. In an embodiment, the inductor 120 can communicate with an external device (not shown) by passive telemetry (e.g., near-field wireless communication) such that power and / or data is transferred between the implant 100 and the external device.

[0046]

[0093] In one embodiment, the buried object locator 101 can be used to locate a buried object 100 (e.g., a buried object 100 embedded in tissue 150 below a skin surface 154 of a living animal). In one embodiment, a first process of locating the buried object 100 can include a first step of determining a midline of the buried object 100. In one embodiment, determining the midline of the buried object 100 can include moving the buried object locator 101 across the longitudinal axis of the buried object 100 (e.g., transverse to the longitudinal axis), as shown in Figures 9A, 10A, and 11A. Figures 9A and 10A respectively show the movement of the buried object locator 101 across the longitudinal axis of the buried object 100 that is not inclined relative to the skin surface, and the movement of the buried object locator 101 across the longitudinal axis of the buried object 100 that is inclined downward. In some embodiments, an orientation of the implant 100 can be assumed (e.g., the longitudinal axis of the implant 100 implanted in the arm of a living animal can be assumed to be approximately along the long axis of the arm), and movement of the implant locator 101 transverse to the longitudinal axis of the implant 100 can be transverse to the assumed orientation of the implant 100. In some embodiments, the orientation of the implant 100 can be determined using records relating to the implantation of the implant 100, and movement of the implant locator 101 transverse to the longitudinal axis of the implant 100 can be transverse to the orientation of the implant 100 determined using the implantation records.

[0047]

[0094] In some embodiments, the search for the buried object 100 may include using the embedded information of the buried object 100. In some embodiments, the embedded information may include embedded location information that identifies where the buried object 100 is embedded, and the embedded location information may be used to identify and / or limit an initial search area for the buried object 100. In some embodiments, the embedded information may additionally or alternatively include embedded depth information that identifies the depth at which the buried object is embedded, and the embedded depth information may be used to estimate an expected signal distance. In embodiments where there is an offset between the center of the magnetic material 124 and the center of the buried object 100, the embedded information may additionally or alternatively include offset direction information that identifies the direction of offset of the center of the magnetic material 124 relative to the center of the buried object 100, and may be used to identify the edge of the buried object 100 and / or the incision site.

[0048]

[0095] In one embodiment, the magnetic material 124 of the implant 100 can cause a change in the magnetic field generated by the magnetic field generator 103 of the implant 101 when the implant 101 is moved across the longitudinal axis of the implant 100, and the sensor 105 of the implant 101 can detect this magnetic field. FIG. 9B shows the change in the magnetic field caused by the magnetic material 124 of the implant 100 that is not tilted relative to the skin surface, as detected by the sensor 105 during movement across the longitudinal axis of the implant 100, according to one embodiment. FIG. 10B and FIG. 14B show the change in the magnetic field caused by the magnetic material 124 of the implant 100 that is tilted out of plane or downward, as detected by the sensor 105 during movement across the longitudinal axis of the implant 100, according to one embodiment. In one embodiment, as shown in Figures 9B, 10B and 14B, the change in magnetic field as the buried object detector 101 is moved across the longitudinal axis of the buried object 100 may be greatest at the midline of the buried object 100.

[0049]

[0096] In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can be configured to determine the midline of the buried object 100 based on where the change in the magnetic field is maximum as the buried object detector 101 is moved across the longitudinal axis of the buried object 100. In one embodiment, the computer 106 of the buried object detector 101 can be configured to determine the derivative of the change in the detected magnetic field, and the computer 106 can be configured to determine the midline of the buried object 100 (and where the change in the magnetic field is maximum) based on where the derivative of the change in the magnetic field during the movement of the sensor 105 across the longitudinal axis of the buried object 100 is equal to zero. In one embodiment, the derivative of the change in the magnetic field can be relative to time (as the sensor 105 is moved across the longitudinal axis of the buried object 100). In some alternative embodiments, the derivative of the change in the magnetic field may be relative to the position of the sensor (as the sensor 105 is traversed across the longitudinal axis of the implant 100).

[0050]

[0097] In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can cause the user interface 127 to indicate when the buried object detector 101 (e.g., the computer 106) detects the midline of the buried object 100 (e.g., when the computer 106 determines that the derivative of the change in the magnetic field during the traversal of the sensor 105 across the longitudinal axis of the buried object 100 is equal to zero). In one embodiment, the user interface 127 can indicate the detection of the midline using one or more of the display 129 (e.g., by displaying a visual indicator indicative of the midline detection), the speaker 131 (e.g., by emitting an audible sound such as, but not limited to, a beep), and the vibration motor 133 (e.g., by vibrating).

[0051]

[0098] 11B shows the detected magnetic field change as the buried object locator 101 is moved across the longitudinal axis of the buried object 100 for the buried object 100 at different heights of the sensor 105 of the buried object locator 101 relative to the buried object 100. As shown in FIG. 11B, the magnitude of the detected magnetic field change increases as the height decreases. Thus, the buried object locator 101 (e.g., the computer 106 of the buried object locator 101) can be configured to use the magnitude of the detected magnetic field change at the midline (e.g., the maximum detected magnetic field change during movement of the sensor 105 across the longitudinal axis of the buried object 100) to determine the depth of the buried object 100 within the tissue 150.

[0052]

[0099] In one embodiment, the first process of locating the buried object 100 can include a second step of determining one or more edges of the magnetic material 124 of the buried object 100 and / or a center of the magnetic material 124 of the buried object 100. In one embodiment, determining the edges and / or center of the magnetic material 124 of the buried object 100 can include moving the buried object locator 101 along the longitudinal axis of the buried object 100, as shown in Figures 9C, 10C, 12A, and 14A. Figure 9C shows the movement of the buried object locator 101 along the longitudinal axis of the buried object 100 that is not inclined relative to the skin surface. Figures 10C and 14A show the movement of the buried object locator 101 along the longitudinal axis of the buried object 100 that is inclined downward or out of plane. In one embodiment, the determined midline can be used to move the buried object locator 101 along the longitudinal axis of the buried object 100. For example, in one embodiment, moving the implant locator 101 along the longitudinal axis of the implant 100 can include moving the implant locator 101 along a determined midline of the implant 100 on the skin surface 154. In one embodiment, the movement along the longitudinal axis of the implant 100 can be parallel to an assumed orientation of the implant 100. In one embodiment, the movement along the longitudinal axis of the implant 100 can be parallel to an orientation of the implant 100 determined using the implant recording.

[0053]

[0100] In one embodiment, the magnetic material 124 of the implant 100 can cause a change in the magnetic field generated by the magnetic field generator 103 of the implant 101 when the implant 101 is moved along the longitudinal axis of the implant 100, and the sensor 105 of the implant 101 can detect the change in the magnetic field. FIG. 9D shows the change in the magnetic field caused by the magnetic material 124 of the implant 100 that is not tilted relative to the skin surface, as detected by the sensor 105 during movement along the longitudinal axis of the implant 100, according to one embodiment. FIG. 10D and FIG. 14C show the change in the magnetic field caused by the magnetic material 124 of the implant 100 that is tilted out of plane or downward, as detected by the sensor 105 during movement along the longitudinal axis of the implant 100, according to one embodiment. In one embodiment, as shown in Figures 9D, 10D, and 14C, the detected change in the magnetic field as the implant detector 101 is moved along the longitudinal axis of the implant 100 may include a bimodal peak (e.g., a local maximum) at the location of the edge of the magnetic material 124 of the implant 100. In one embodiment, as shown in Figures 9D, 10D, and 14C, the change in the magnetic field may include a local minimum between the bimodal peaks at the location of the center of the magnetic material 124 of the implant 100.

[0054]

[0101] In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can be configured to determine the edge of the magnetic material 124 of the buried object 100 based on the location of the bimodal peak in the change in the magnetic field. In one embodiment, the computer 106 of the buried object detector 101 can be configured to determine the derivative of the change in the detected magnetic field, and the computer 106 can be configured to determine the edge of the magnetic material 124 of the buried object 100 (and the location of the bimodal peak in the change in the magnetic field) based on the location where the derivative of the change in the magnetic field equals zero during the movement of the sensor 105 along the longitudinal axis of the buried object 100. In one embodiment, the derivative of the change in the magnetic field can be relative to time (as the sensor 105 is moved along the longitudinal axis of the buried object 100). In another embodiment, the derivative of the change in the magnetic field can be relative to the position of the sensor (as the sensor 105 is moved along the longitudinal axis of the buried object 100). In some embodiments, the edge of the magnetic material 124 of the implant 100 may be offset from the edge of the implant 100. For example, the edge of the magnetic material 124 of the implant 100 is offset from the edge of the implant 100. In some embodiments where the edge of the magnetic material 124 is offset from the edge of the implant 100, the implant detector 101 (e.g., the computer 106 of the implant detector 101) can be configured to determine one or more edges of the implant 100 using one or more determined edges of the magnetic material 124 and offsets.

[0055]

[0102] In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can be configured to determine the center of the magnetic material 124 of the buried object 100 based on the location of a local minimum in the magnetic field change between the bimodal peaks in the magnetic field change. In one embodiment, the computer 106 of the buried object detector 101 can be configured to determine the derivative of the detected magnetic field change, and the computer 106 can be configured to determine the center of the magnetic material 124 of the buried object 100 (and the local minimum between the bimodal peaks in the magnetic field change) based on the location where the derivative of the magnetic field change equals zero during the movement of the sensor 105 along the longitudinal axis of the buried object 100. In one embodiment, the center of the magnetic material 124 of the buried object 100 may be offset from the center of the buried object 100 (i.e., the center of the magnetic material 124 may be different from the center of the buried object 100). For example, in the implant 100 shown in FIG. 8A, the center of the magnetic material 124 of the implant 100 is offset (e.g., by 2.5 mm) from the center of the implant 100. In an embodiment where the magnetic material 124 is offset from the center of the implant 100, the implant locator 101 (e.g., the computer 106 of the implant locator 101) can be configured to use the determined center and offset of the magnetic material 124 to determine the center of the implant 100. In an embodiment, a direction of offset of the center of the magnetic material 124 relative to the center of the implant 100 can be assumed (e.g., the center of the magnetic material 124 can be assumed to be higher than the center of the implant 100 along the long axis of the arm). In certain embodiments, additionally or alternatively, the direction of offset of the center of the magnetic material 124 relative to the center of the implant 100 can be ascertained or determined (e.g., using embedded recording and / or detected magnetic field changes caused by metal and / or circuitry on and / or within the substrate 110, which may extend from one side of the magnetic material 124 of the implant 100 as shown in Figures 8A and 8B).

[0056]

[0103] In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can cause the user interface 127 to indicate when the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) has detected an edge and / or a center of the magnetic material 124 of the buried object 100 (e.g., when the computer 106 determines that the derivative of the change in the magnetic field during movement of the sensor 105 along the longitudinal axis of the buried object 100 is equal to zero). In one embodiment, the user interface 127 can indicate the edge and / or center detection using one or more of the display 129 (e.g., by displaying a visual indicator indicative of edge and / or center detection), the speaker 131 (e.g., by emitting an audible sound such as, by way of example and not limitation, a beep), and the vibration motor 133 (e.g., by vibrating).

[0057]

[0104] 12B shows the detected magnetic field change when the buried object locator 101 is moved along the longitudinal axis of the buried object 100 for the buried object 100 at different heights of the sensor 105 of the buried object locator 101 relative to the buried object 100. As shown in FIG. 12B, the magnitude of the detected magnetic field change at the bimodal peaks increases as the height decreases. Thus, the buried object locator 101 (e.g., the computer 106 of the buried object locator 101) can be configured to use the magnitude of the detected magnetic field change at one or more of the bimodal peaks (e.g., the local maximum of the detected magnetic field change during the movement of the sensor 105 along the longitudinal axis of the buried object 100) to determine the depth of the buried object 100 within the tissue 150. In some embodiments, the buried object locator 101 may additionally or alternatively use the magnitude of the magnetic field change at the midline of the buried object 100 to determine the depth of the buried object 100 within the tissue 150.

[0058]

[0105] In an embodiment, as shown in FIG. 9D, for an implant 100 having a longitudinal axis that is not tilted relative to the skin surface and extends parallel to the skin surface 154, the magnitude of the magnetic field change at the bimodal peaks may be equal (or approximately equal, for example, but not limited to, within 2 or 3 Oersteds (Oe)). In an embodiment, as shown in FIG. 10D and FIG. 14C, the magnitude of the magnetic field change at the bimodal peaks may be different for an implant 100 having a longitudinal axis that is not parallel to the skin surface 154 (e.g., for an implant 100 that is tilted downward). In an embodiment, the implant locator 101 (e.g., the computer 106 of the implant locator 101) can use the magnitude of the magnetic field change at the bimodal peaks to determine the orientation of the implant 100. In an embodiment, determining the orientation can include calculating a difference between the magnitudes of the magnetic field change at the bimodal peaks and calculating the angle of the implant 100 relative to the skin surface 154 based on the calculated difference. In one embodiment, determining the orientation of the implant 100 may additionally or alternatively include using the magnitude of the magnetic field change at the bimodal peak to calculate the depth of the edge of the magnetic material 124 (and / or the edge of the implant 100).

[0059]

[0106] In an embodiment, the implant locator 101 (e.g., the computer 106 of the implant locator 101) can be configured to cause the user interface 127 (e.g., the display 129 of the user interface 127) to provide information indicative of the location and / or orientation of the implant 100. In an embodiment, the information indicative of the location and / or orientation of the implant 100 can include information indicative of the midline of the implant 100, one or more edges of the magnetic material 124, one or more edges of the implant 100, the center of the magnetic material 124, the center of the implant 100, the depth of the implant 100 within the tissue 150, the orientation of the implant 100, and / or the location of an incision for removal of the implant 100. In an embodiment, the information indicative of the orientation of the implant 100 can include an indication of the angle of the implant 100, the depth of the edge of the magnetic material 124, and / or the depth of the edge of the implant 100. In some embodiments, the information indicative of the location and / or orientation of the buried object 100 may include a buried object image 704 (e.g., as shown in FIGS. 7B-7F). In some embodiments, the information indicative of the location and / or orientation of the buried object 100 may include one or more plots of the change in the magnetic field during the movement / sweep of the buried object detector 101 (e.g., the plots shown in FIGS. 9B, 9D, 10B, 10D, 13B-13E, 14B, 14C). In some embodiments, the plots may show one or more peaks of the magnetic field change (e.g., depending on whether the movement is transverse, along, or oblique to the longitudinal axis of the buried object 100).

[0060]

[0107] 9E and 10E, the first process for locating the implant 100 can include a third step of marking an incision location to remove the implant 100. In some embodiments, the incision location can be marked using the incision marking tool 113 of the implant locator 101 (e.g., when the sensor 105 of the implant locator 101 is positioned over the center of the implant 100, over the center of the magnetic material 124 of the implant 100, and / or with the edge of the magnetic field generator 103 positioned over the edge of the magnetic material 124 of the implant 100).

[0061]

[0108] In one embodiment, as shown in FIG. 13A, the buried object detector 101 may be moved diagonally (e.g., at a 45 degree angle, or at a smaller angle, such as, but not limited to, 10 degrees, 15 degrees, 20 degrees, 25 degrees, or 30 degrees) with respect to the longitudinal axis of the buried object 100 (e.g., when the user is trying to search for the buried object 100 and / or when the user accidentally moves the buried object detector 101 along the longitudinal axis). FIG. 13B shows the change in the detected magnetic field when the buried object detector 101 is moved diagonally with respect to the longitudinal axis of the buried object 100. FIGS. 13C-13E show the X, Y, and Z components of the magnetic field change when the buried object detector 101 is moved diagonally with respect to the longitudinal axis of the buried object 100. In one embodiment, the location of the maximum magnitude of the magnetic field change can be used to determine the midline of the buried object 100. In one embodiment, the movement / scanning direction of the buried object locator 101 can be changed until the orientation of the buried object 100 (eg, the longitudinal axis of the buried object 100) is found.

[0062]

[0109] In some embodiments, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can be configured to control a user interface 127 (e.g., a display 129) to output information indicative of the sensor signal generated by the sensor 105 (and thus indicative of detected changes in the magnetic field caused by the magnetic material 124 of the buried object 100). In some embodiments, the information indicative of the sensor signal can be simultaneously used by a user (e.g., a clinician) to determine the approximate location of the buried object 100.

[0063]

[0110] In some embodiments, a second process can be used to locate the buried object 100. In some embodiments, the second process can be used if the first process (described above with respect to FIGS. 9A-10E) does not reveal a double / bimodal peak pattern that is present when the buried object locator 101 is moved along the longitudinal axis of the buried object 100. In some embodiments, the second process can include a first step of finding the "best" orientation of the longitudinal axis of the buried object 100. In some embodiments, as shown in FIG. 15A, the first step can include moving the buried object locator 101 at different angles (e.g., in incremental angles of 15 degrees) until a double / bimodal peak pattern is identified.

[0064]

[0111] In one embodiment, as shown in FIG. 15B, the second process can include a second step of identifying the center of the magnetic material 124 of the implant 100. In one embodiment, the second step can include moving the implant locator 101 along the longitudinal axis identified in the first step. In one embodiment, as shown in FIG. 9D, FIG. 10D, and FIG. 14C, the change in the magnetic field detected when the implant locator 101 is moved along the longitudinal axis of the implant 100 can include a bimodal peak (e.g., a local maximum) at the location of the edge of the magnetic material 124 of the implant 100. In one embodiment, the center of the magnetic material 124 can be identified by finding a local maximum of the magnetic field change between the bimodal peaks in the magnetic field change. In one embodiment, the computer 106 of the buried object locator 101 can be configured to determine the derivative of the change in the detected magnetic field, and the computer 106 can be configured to determine the center of the magnetic material 124 of the buried object 100 (and the location of the local minimum between two peaks of the magnetic field change) based on where the derivative of the change in the magnetic field during movement of the sensor 105 along the longitudinal axis of the buried object 100 equals zero. In one embodiment, the buried object locator 101 (e.g., the computer 106 of the buried object locator 101) can be configured to cause the user interface 127 to provide an indication of the center of the magnetic material 124. In one embodiment, the indication of the center of the magnetic material 124 can include a plot of the magnetic field change during the sweep, and / or a visual (e.g., a flashing light), audible (e.g., a beep), or vibration indication when the derivative of the magnitude of the magnetic field change between the bimodal peaks is zero.

[0065]

[0112] In an embodiment, the second process can include a third step in which the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) calculates the depth and / or orientation (e.g., downward angulation) of the buried object 100. In an embodiment, the buried object detector 101 can calculate the depth and / or orientation of the buried object 100 using the magnitude of the magnetic field change at the bimodal peak and / or the difference between the magnitudes of the magnetic field change at the bimodal peak. In an embodiment, the buried object detector 101 can calculate the depth and / or orientation of the buried object 100 in response to a user input (e.g., a button press) received via a user input 135 of the user interface 127. In an embodiment, the buried object detector 101 can cause the user interface 127 (e.g., the display 129 of the user interface 127) to provide the calculated depth and / or orientation of the buried object 100 to a user (e.g., a clinician).

[0066]

[0113] In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can use a data library to calculate the depth and / or orientation (e.g., downward angulation) of the buried object 100 in order to map the sensor signal generated by the sensor 105 during one or more movements / sweeps of the buried object detector 101 to the depth and / or orientation. In one embodiment, the library can include sensor signal curve characteristics of a particular orientation of the buried object 100. In one embodiment, the characteristic curve can be identified by experiment. In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can compare the sensor signal generated by the sensor 105 during one or more movements / sweeps of the buried object detector 101 to a particular curve. In one embodiment, the buried object detector 101 can determine that the buried object 100 has an approximate buried object orientation (e.g., in-plane and / or out-of-plane angulation) associated with the characteristic curve to which the generated sensor signal is most similar. In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can calculate the depth (or estimated depth range) using the magnitude of the sensor signal generated during the movement / sweep (e.g., at one or more peaks thereof).

[0067]

[0114] In one embodiment, if the buried object locator 101 determines that the sensor signal generated by the sensor 105 during the movement of the buried object locator 101 indicates in-plane angulation (e.g., indicates that the movement / sweep direction is oblique to the longitudinal axis of the buried object 100), the third step of the second process can include the buried object locator 101 (e.g., the computer 106 of the buried object locator 101) determining a proposed correction to the movement / sweep direction. In one embodiment, the proposed correction can be a specific angle relative to a set direction (e.g., the long axis of the arm) or an angle change (e.g., +5° or −15°) relative to the current / recent movement direction. In one embodiment, the buried object locator 101 can have the user interface 127 (e.g., the display 129 of the user interface 127) provide the user with the proposed correction to the movement / sweep direction. In one embodiment, the movement / sweep direction can be adjusted until the generated sensor signal appears as close as possible to the baseline. In one embodiment, if a single peak still exists in the generated sensor signal, the single peak is likely due to out-of-plane angulation, which cannot be corrected by adjusting the sweep direction.

[0068]

[0115] In one embodiment, as shown in FIG. 15C, a third step of the second process can include marking the edges of the implant (e.g., using an instrument attached to the outer edge of the magnetic field generator 103) and / or marking the incision location (e.g., using the incision marking tool 113).

[0069]

[0116] In one embodiment, a third process can be used to locate the buried object 100. In one embodiment, the third process can include a first step of locating the approximate location of the longitudinal axis of the buried object 100. In one embodiment, as shown in FIG. 16A, the first step can include moving the buried object locator 101 along the skin surface 154 and searching for any signals. In one embodiment, the buried object 100 can be located in the area where the signal is found.

[0070]

[0117] In one embodiment, as shown in FIG. 16B, the third process can include a second step in which a template 1601 (e.g., a template sticker) is placed over the area where the signal was found. In one embodiment, as shown in FIG. 16B, the template 1601 can include marks (e.g., numbers) that serve as waypoints that specify the course of movement / sweep of the buried object detector 101. For example, in one embodiment, the template 1601 can specify a course of waypoints such as, but not limited to, 9 to 3, 4 to 10, 11 to 5, 6 to 12, 1 to 7, and 8 to 2. In one embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can cause the user interface 127 (e.g., the display 129) to provide instructions for the course of movement / sweep of the buried object detector 101 using the template 1601. In one embodiment, a second step of the third process can include moving the buried object detector 101 along a course specified by the template 1601. In one embodiment, the second step of the third process can culminate with the movement of the buried object detector 101 to a final position above the template 1601.

[0071]

[0118] In one embodiment, the third process may include a third step in which the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) calculates the depth and / or orientation (e.g., in-plane angulation and / or out-of-plane angulation) of the buried object 100. In one embodiment, the buried object detector 101 may calculate the depth and / or orientation of the buried object 100 using a sensor signal generated by the sensor 105 indicative of a magnetic field change caused by the magnetic material 124 of the buried object 100 when the buried object detector 101 is moved along a course specified by the template 1601. In an embodiment, the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) can calculate the depth and / or orientation of the buried object 100 using a data library to map the sensor signal generated by the sensor 105 to a depth and / or orientation as the buried object detector 101 is moved along a course specified by the template 1601. In an embodiment, the buried object detector 101 can calculate the depth and / or orientation of the buried object 100 in response to a user input (e.g., a button press) received via a user input 135 of the user interface 127. In an embodiment, the buried object detector 101 can provide the calculated depth and / or orientation of the buried object 100 to a user (e.g., a clinician) on the user interface 127 (e.g., the display 129 of the user interface 127).

[0072]

[0119] In one embodiment, as shown in FIG. 16C, the buried object detector 101 can display a buried object image 704 and / or a template image 1603 on the screen 702 of the display 129. In one embodiment, as shown in FIG. 16C, the location of the buried object image 704 relative to the template image 1603 on the screen 704 of the display 129 can correspond to the detected location of the buried object 100 relative to the template 1601. In one embodiment, as shown in FIG. 16C, the buried object image 704 can have an orientation that corresponds to the calculated orientation of the buried object 100. In one embodiment, the buried object image 704 can show the in-plane angulation and / or the out-of-plane (e.g., downward) angulation of the calculated orientation. In one embodiment, the buried object image 704 can additionally or alternatively show the calculated depth.

[0073]

[0120] In one embodiment, the third step of the third process may additionally or alternatively include the buried object detector 101 (e.g., the computer 106 of the buried object detector 101) calculating one or more edges, centers and / or incision locations of the buried object 100. In one embodiment, the buried object detector 101 may calculate one or more buried object edges, centers and / or incision locations using a sensor signal generated by the sensor 105 indicative of a magnetic field change caused by the magnetic material 124 of the buried object 100 when the buried object detector 101 is moved along a course specified by the template 1601. In one embodiment, the buried object detector 101 may calculate one or more buried object edges and / or incision locations using a calculated depth and / or orientation of the buried object 100. In one embodiment, the implant locator 101 can cause the user interface 127 (e.g., the display 129 of the user interface 127) to provide the calculated implant edge(s), implant center(s), and / or incision location(s) to a user (e.g., a clinician). In one embodiment, as shown in FIG. 16C, the implant locator 101 can display the calculated implant edge(s), implant center(s), and / or incision location(s) as coordinates on the screen 702 of the display 129.

[0074]

[0121] FIG. 17 is a flow chart illustrating a process 1700 for exploring an implant 100 including a magnetic material 124, according to an embodiment. In an embodiment, the process 1700 can include a step 1702 of using a magnetic field generator 103 to generate a magnetic field. In an embodiment, the magnetic field generator 103 can include one or more magnets 109. In an embodiment, the magnetic field generator 103 can include a cylindrical magnet 109 (e.g., a hollow cylindrical magnet). In an embodiment, the magnetic field generator 103 can include two or more magnets 109 (e.g., four or six magnets). In an embodiment, the magnetic field generator 103 can include a housing 107 configured to accommodate the two or more magnets 109. In an embodiment, the magnetic field generated by the magnetic field generator 103 can be a substantially uniform magnetic field.

[0075]

[0122] In some embodiments, the process 1700 can include a step 1704 of using the sensor 105 to detect a change in the magnetic field and generate a sensor signal indicative of the change in the magnetic field. In some embodiments, the magnetic material 124 of the implant 100 can cause a change in the magnetic field when the sensor 105 is moved over the implant 100. In some embodiments, the magnetic field can be substantially symmetric about a longitudinal axis at the center of the magnetic field generator 103. In some embodiments, the sensor 105 can be positioned along or offset from the longitudinal axis at the center of the magnetic field generator 103.

[0076]

[0123] In an embodiment, the process 1700 can include step 1706 of using the computer 106 to detect the location of the implant 100 based on the sensor signal. In an embodiment, step 1706 can include the computer 106 causing the user interface 127 to provide an output indicative of the sensor signal. In an embodiment, a user (e.g., a clinician) can use the output sensor signal to detect the location of the implant 100. In an embodiment, step 1706 can include the computer 106 causing the user interface 127 to provide an indication indicative of a time point when a derivative of a change in the magnetic field during movement of the sensor 105 across a longitudinal axis of the implant 100 is equal to zero. In an embodiment, an indication indicative of a derivative of a change in the magnetic field during movement of the sensor 105 across a longitudinal axis of the implant 100 is equal to zero can indicate the location of the implant 100.

[0077]

[0124] In an embodiment, step 1706 may additionally or alternatively include the computer 106 determining the edge of the magnetic material 124 of the implant 100 based on the location of a bimodal peak in the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the implant 100. In an embodiment, the computer 106 may determine the edge of the implant 100 based on the determined edge of the magnetic material 124 of the implant 100 and one or more offsets between the edge of the implant 100 and the edge of the magnetic material 124 of the implant 100. In an embodiment, the computer 106 may be configured to calculate a derivative of the change in the magnetic field and to use the calculated derivative to detect the location of the implant 100. In an embodiment, the computer 106 may be configured to determine the edge of the magnetic material 124 of the implant 100 based on the location where the derivative of the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the implant 100 is equal to zero.

[0078]

[0125] In some embodiments, step 1706 may additionally or alternatively include computer 106 determining a midline of implant 100. In some embodiments, computer 106 may be configured to determine the midline based on where the derivative of the change in magnetic field during movement of sensor 105 across the longitudinal axis of implant 100 is equal to zero.

[0079]

[0126] In one embodiment, the process 1700 can include a step in which the computer 106 determines the depth of the buried object 100 based on the magnitude of the change in the magnetic field at a bimodal peak in the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the buried object 100. In one embodiment, the computer 106 can determine the depth of the buried object 100 based on the magnitude of the change in the magnetic field at a location where the derivative of the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the buried object 100 is equal to zero.

[0080]

[0127] In one embodiment, the process 1700 may additionally or alternatively include a step in which the computer 106 determines the orientation of the implant 100. In one embodiment, the computer 106 may determine the orientation based on a difference between the magnitude of the change in the magnetic field at the bimodal peaks of the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the implant 100. In one embodiment, the computer 106 may determine the orientation of the implant 100 based on a difference between the magnitude of the change in the magnetic field at a location where the derivative of the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the implant 100 is equal to zero.

[0081]

[0128] In an embodiment, the process 1700 may additionally or alternatively include causing the computer 106 to cause the display 129 to display a display indicating the detected location of the buried object 100. In an embodiment, the display of the detected location of the buried object 100 may include a buried object image 704, and the location of the buried object image 704 on the screen 702 of the display 129 relative to a point 706 on the screen 702 of the display 129 may correspond to the detected location of the buried object 100 relative to the sensor 105. In an embodiment, the buried object image 704 may have an orientation corresponding to the detected orientation of the buried object 100.

[0082]

[0129] In an embodiment in which the buried object detector 101 includes a position detector 137 configured to generate a location signal indicative of a location of the sensor 105, the process 1700 may additionally or alternatively include the computer 106 using the sensor signal and the location signal (e.g., a motion signal generated by a motion detector of the position detector 137 indicative of movement of the sensor 105) to generate a map of the sensor signal at different locations of the sensor 105. In an embodiment, generating the map of the sensor signal at different locations of the sensor may include, for example but not limited to, measuring the sensor signal at each of two or more different locations of the sensor 105 and storing the measured sensor signal with an identification of the location at which the sensor signal was measured. In an embodiment, generating the map of the sensor signal at different locations of the sensor 105 may include generating a visualization of the measured sensor signal at the different locations of the sensor 105.

[0083]

[0130] In some embodiments, process 1700 can include the optional step of removing implant 100. In some embodiments, removing implant 100 can include making an incision at an identified edge of implant 100. In some embodiments, removing implant 100 can include grasping implant 100 (e.g., using forceps) and pulling implant 100 out of the body through the incision.

[0084]

[0131] 18 is a flow chart illustrating a process 1800 for locating an implant 100 including a magnetic material 124, according to an embodiment. In an embodiment, the process 1800 can include a step 1802 of moving an apparatus (e.g., an implant locator 101) including a magnetic field generator 103 and a sensor 105 across a longitudinal axis of the implant 100. In an embodiment, the magnetic material 124 of the implant 100 can cause a change in the magnetic field generated by the magnetic field generator 103 when the apparatus is moved across the longitudinal axis of the implant 100, and the sensor 105 can detect the change in the magnetic field. In an embodiment, the process 1800 can include a step 1804 of determining a midline of the implant 100 based on where the change in the magnetic field is maximum when the apparatus is moved across the longitudinal axis of the implant 100. In an embodiment, the process 1800 can include a step 1806 of moving the apparatus along the determined midline of the implant 100. In some embodiments, the process 1800 can include a step 1808 of determining an edge of the magnetic material 124 of the implant 100 based on the location of the bimodal peak in the change in the magnetic field. In some embodiments, the process 1800 can include an operational step of using an incision marking tool 1113 of the device to mark an incision location for removing the implant 100. In some embodiments, the process 1800 can include an optional step of removing the implant 100. In some embodiments, removing the implant 100 can include making an incision at the incision location. In some embodiments, removing the implant 100 can include grasping the implant 100 (e.g., using forceps) and pulling the implant 100 out of the body through the incision.

[0085]

[0132] In an embodiment, as shown in FIG. 19, the implant 100 can include a plurality of analyte indicators 104 (e.g., a first analyte indicator 104a and a second analyte indicator 104b). In an embodiment, as shown in FIG. 19, the implant 100 can include a charge storage device 202 (e.g., a battery). In an embodiment, the charge storage device 202 can be a battery having a metal housing (e.g., a titanium housing). In an embodiment, the charge storage device 202 can be attached to the housing 102. In an embodiment, a coupler 324 can be attached to the housing 102 and the charge storage device 202. In an embodiment, the coupler 324 can be between the housing 102 and the charge storage device 202. In an embodiment, as shown in FIG. 19, the coupler 324 can include one or more supports 232 (e.g., a reinforcing rod, bar, or beam) that can be attached to and / or integrated with the coupler 324. In some embodiments, the implant 100 can include first and second conductive connectors that connect the positive and negative poles of the charge storage device 202 to a circuit of the implant 100. In some embodiments, the circuit of the implant 100 can extend along a longitudinal axis of the charge storage device 202 in a direction away from the charge storage device 202, as shown in FIG. 19. In some embodiments, the circuit of the implant 100 can include an inductor 120, which can include a conductor 122 and a magnetic material 124 in the form of a magnetic core. In some embodiments, the charge storage device 202 can include a first edge at one end of the implant 100 and a second edge adjacent the coupler 324 and / or the housing 102, as shown in FIG. 19. In some embodiments, the second edge of the charge storage device 202 can be located in a central region of the implant 100.

[0086]

[0133] In certain embodiments, the implant 100 may include one or more drug eluting polymer matrices 730 and 732. In certain embodiments, the one or more drug eluting polymer matrices 730 and 732 may be in or on a portion of the exterior surface of the housing 102 of the implant 100. In certain embodiments, one or more therapeutic agents may be dispersed within the one or more drug eluting polymer matrices 730 and 732. In certain embodiments, the one or more therapeutic agents may reduce or prevent neutrophil migration into the space in which the implant is implanted, thus reducing or preventing the production of hydrogen peroxide and fibrous encapsulation. Thus, in certain embodiments, the one or more therapeutic agents may reduce the degradation of one or more analyte indicators 104 (e.g., the first analyte indicator 104a and the second analyte indicator 104b). In certain embodiments, one or more therapeutic agents may be dispersed within the one or more drug-eluting polymer matrices 730 and 732 and may include, for example, one or more anti-inflammatory agents, such as nonsteroidal anti-inflammatory agents (e.g., acetylsalicylic acid (aspirin) and / or isobutylphenylpropanoic acid (ibuprofen)). In certain embodiments, the one or more therapeutic agents dispersed within the one or more drug-eluting polymer matrices 730 and 732 may include one or more glucocorticoids. In certain embodiments, the one or more therapeutic agents may include one or more of dexamethasone, triamcinolone, betamethasone, methylprednisolone, beclomethasone, fludrocortisone, derivatives thereof, and analogs thereof. In certain embodiments, the one or more therapeutic agents may reduce hydrogen peroxide production by neutrophils and macrophages.

[0087]

[0134] In some embodiments (e.g., some embodiments in which the buried object 100 includes a charge storage device 202), as shown in FIG. 20, the magnetic field generator 103 of the buried object detector 101 can be an electromagnetic field generator 103' configured to generate an electromagnetic field. In some embodiments, the electromagnetic field can include a low frequency (e.g., a very low frequency (VLF) wave). In some embodiments, the low frequency can have a frequency in a range between, for example, but not limited to, 3 kHz and 30 kHz. In some embodiments, the low frequency can have a frequency in a range between, for example, but not limited to, 5 kHz and 15 kHz. In some embodiments, the sensor 105 of the buried object detector 101 can be configured to detect a change in the electromagnetic field and to generate a sensor signal indicative of the change in the electromagnetic field. In some embodiments, at least the charge storage device 202 of the buried object 100 can cause a change in the electromagnetic field when the sensor 105 is moved over the buried object 100. In one embodiment, the computer 106 of the buried object detector 101 can be configured to use the sensor signal to detect the location of the buried object 100 .

[0088]

[0135] In some electromagnetic field embodiments, as shown in FIGS. 21A and 21B, the electromagnetic field generator 103′ can include one or more electromagnets 109′. In some embodiments, the one or more electromagnets 109′ can be, for example, but not limited to, a coil of wire wound around a magnetic core made of a ferromagnetic or ferrimagnetic material. In some embodiments, the electromagnetic field generator 103′ can provide an alternating current to the one or more electromagnets 109′. The alternating current can have a frequency, for example, but not limited to, within a range between 3 kHz and 30 kHz, or more specifically, within a range between 5 kHz and 15 kHz. In some embodiments, as shown in FIG. 21C, the electromagnetic field generator 103′ can include a housing 107, which can be configured to hold the one or more electromagnets 109. However, the housing 107 is not required, and in some alternative embodiments (e.g., some embodiments in which the electromagnetic field generator 103′ consists of only a single electromagnet 109′), the electromagnetic field generator 103′ can not include the housing 107. In one embodiment, the sensor 105 can be positioned on the longitudinal axis at the center of the electromagnetic field generator 103', as shown in Figures 21A and 21B. However, this is not required, and in one alternative embodiment, the sensor 105 is not positioned on the longitudinal axis at the center of the electromagnetic field generator 103'. For example, the sensor 105 may be positioned adjacent to an electromagnet 109' of the electromagnetic field generator 103' (rather than at the center of one or more electromagnets 109' of the electromagnetic field generator 103'). See Figure 3A.

[0089]

[0136] 22 is a flow chart illustrating a process 2200 for exploring a buried object 100 including a charge storage device 202, according to an embodiment. In an embodiment, the process 2200 can include a step 2202 of using an electromagnetic field generator 103′ to generate an electromagnetic field. In an embodiment, the electromagnetic field generator 103′ can include one or more electromagnets 109′. In an embodiment, the electromagnetic field generator 103′ can include a cylindrical electromagnet 109′ (e.g., a hollow cylindrical electromagnet). In another embodiment, the electromagnetic field generator 103′ can include two or more electromagnets 109′ (e.g., four or six electromagnets). In an embodiment, the electromagnetic field generator 103′ can include a housing 107 configured to accommodate the one or more electromagnets 109′.

[0090]

[0137] In an embodiment, the process 2200 can include a step 2204 of using the sensor 105 to detect a change in the electromagnetic field and generate a sensor signal indicative of the change in the electromagnetic field. In an embodiment, at least the charge storage device 202 of the implant 100 can cause a change in the electromagnetic field as the sensor 105 is moved over the implant 100. In an embodiment, the electromagnetic field can be substantially symmetric about a central longitudinal axis of the electromagnetic field generator 103'. In an embodiment, the sensor 105 can be positioned along or offset from the central longitudinal axis of the electromagnetic field generator 103'.

[0091]

[0138] In an embodiment, the process 2200 can include a step 2206 of using the computer 106 to detect the location of the implant 100 based on the sensor signal. In an embodiment, the step 2206 can include the computer 106 causing the user interface 127 to provide an output indicative of the sensor signal. In an embodiment, the output sensor signal can be used by a user (e.g., a clinician) to detect the location of the implant 100. In an embodiment, the step 2206 can include the computer 106 causing the user interface 127 to provide an indication indicative of a time point when a derivative of a change in the electromagnetic field during movement of the sensor 105 across a longitudinal axis of the implant 100 is equal to zero. In an embodiment, an indication indicative of a derivative of a change in the electromagnetic field during movement of the sensor 105 across a longitudinal axis of the implant 100 is equal to zero can indicate the location of the implant 100.

[0092]

[0139] In an embodiment, step 2206 may additionally or alternatively include the computer 106 determining an edge of the charge storage device 202 of the implanted object 100 based on a location of a bimodal peak in the change in the electromagnetic field during the movement of the sensor 105 along the longitudinal axis of the implanted object 100. In an embodiment, the computer 106 may determine one or more edges of the implanted object 100 based on the determined edges of the charge storage device 202 of the implanted object 100. In an embodiment, the computer 106 may be configured to calculate a derivative of the change in the electromagnetic field and to use the calculated derivative to detect the location of the implanted object 100. In an embodiment, the computer 106 may be configured to determine an edge of the charge storage device 202 of the implanted object 100 based on a location where the derivative of the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the implanted object 100 is equal to zero.

[0093]

[0140] In an embodiment, the magnitude of the bimodal peak of the electromagnetic field change at a first edge of the charge storage device 202 at the edge of the implant 100 can be greater than the magnitude of the bimodal peak of the electromagnetic field change at a second edge of the charge storage device 202 adjacent to the coupler 324 and / or the housing 102. In an embodiment, the magnetic material 124 in the housing 102 of the implant 100 can cause the magnitude of the bimodal peak of the electromagnetic field change at the second edge of the charge storage device 202 to be lower than the magnitude of the bimodal peak of the electromagnetic field change at the first edge of the charge storage device 202. In an embodiment, the computer 106 can be configured to determine which of the bimodal peaks of the electromagnetic field change has a greater magnitude. In an embodiment, the computer 106 can be configured to determine that the first edge of the charge storage device 202 is at the location of the bimodal peak having the greater magnitude. In an embodiment, the computer 106 can determine that one edge of the implant 100 is at the first edge of the charge storage device 202. In some embodiments, the incision location for removing the implant 100 may be at or near the location of the bimodal peak in the change in the electromagnetic field having the greater magnitude.

[0094]

[0141] In an embodiment, the computer 106 can additionally or alternatively be configured to determine a second edge of the implant 100. In an embodiment, the computer 106 can determine the second edge of the implant 100 using a location of the second edge of the charge storage device 202 (e.g., a location of a bimodal peak in the change in the electromagnetic field having a smaller magnitude) and a displacement between the second edge of the charge storage device 202 and an end of the housing 102. In an embodiment, the second edge of the charge storage device 202 can be an edge of the charge storage device 202 adjacent to the coupler 324 and / or the housing 102.

[0095]

[0142] In some embodiments, step 2206 may additionally or alternatively include computer 106 determining a midline of implant 100. In some embodiments, computer 106 may be configured to determine the midline based on where the derivative of the change in magnetic field during movement of sensor 105 across the longitudinal axis of implant 100 is equal to zero.

[0096]

[0143] In one embodiment, the process 2200 can include the computer 106 determining the depth of the buried object 100 based on the magnitude of the change in the electromagnetic field at a bimodal peak in the change in the magnetic field during the movement of the sensor 105 along the longitudinal axis of the buried object 100. In one embodiment, the computer 106 can determine the depth of the buried object 100 based on the magnitude of the change in the electromagnetic field at a location where the derivative of the change in the electromagnetic field during the movement of the sensor 105 along the longitudinal axis of the buried object 100 is equal to zero.

[0097]

[0144] In an embodiment, the process 2200 may additionally or alternatively include a step in which the computer 106 determines the orientation of the implant 100. In an embodiment, the computer 106 may determine the orientation based on a difference between the magnitudes of the electromagnetic field change at the bimodal peaks of the change in the electromagnetic field during movement of the sensor 105 along the longitudinal axis of the implant 100 (e.g., after taking into account an expected difference between the magnitudes of the bimodal peaks due to the second edge of the charge storage device 202 being closer to the magnetic material 124 in the housing 102). In an embodiment, the computer 106 may determine the orientation of the implant 100 based on a difference between the magnitudes of the electromagnetic field change at the locations where the derivative of the change in the electromagnetic field during movement of the sensor 105 along the longitudinal axis of the implant 100 is equal to zero (e.g., after taking into account a decrease in the magnitude of the bimodal peaks of the electromagnetic field change at the second edge of the charge storage device 202 that may result from the second edge of the charge storage device 202 being closer to the magnetic material 124).

[0098]

[0145] In an embodiment, the process 2200 may additionally or alternatively include causing the computer 106 to display on the display 129 a representation of the detected location of the buried object 100. See, for example, FIG. 1 and FIG. 7A-7F. In an embodiment, the representation of the detected location of the buried object 100 may include a buried object image 704, and the location of the buried object image 704 on the screen 702 of the display 129 relative to a point 706 on the screen 702 of the display 129 may correspond to the detected location of the buried object 100 relative to the sensor 105. In an embodiment, the buried object image 704 may have an orientation that corresponds to the detected orientation of the buried object 100.

[0099]

[0146] In an embodiment in which the object detector 101 includes a position detector 137 configured to generate a location signal indicative of a location of the sensor 105, the process 2200 may additionally or alternatively include the computer 106 using the sensor signal and the location signal (e.g., a motion signal generated by a motion detector of the position detector 137 indicative of movement of the sensor 105) to generate a map of the sensor signal at different locations of the sensor 105. In an embodiment, generating the map of the sensor signal at different locations of the sensor may include, for example but not limited to, measuring a sensor signal at each of two or more different locations of the sensor 105 and storing the measured sensor signal with an identification of the location at which the sensor signal was measured. In an embodiment, generating the map of the sensor signal at different locations of the sensor 105 may include generating a visualization of the measured sensor signal at the different locations of the sensor 105.

[0100]

[0147] In some embodiments, the process 2200 can include an optional step of removing the implant 100. In some embodiments, removing the implant 100 can include making an incision at an identified edge of the charge storage device 202. In some embodiments, removing the implant 100 can include grasping the charge storage device 202 of the implant 100 (e.g., using forceps), which may be stronger than the housing 102 of the implant 100, and pulling the implant 100 out of the body through the incision.

[0101]

[0148] 23 is a flow chart illustrating a process 2300 for locating a buried object 100 including a charge storage device 202, according to an embodiment. In an embodiment, the process 2300 can include a step 2302 of moving an apparatus (e.g., a buried object detector 101) including an electromagnetic field generator 103′ and a sensor 105 across a longitudinal axis of the buried object 100. In an embodiment, at least the charge storage device 202 of the buried object 100 can cause a change in an electromagnetic field generated by the electromagnetic field generator 103′ when the apparatus is moved across the longitudinal axis of the buried object 100, and the sensor 105 can detect the change in the electromagnetic field. In an embodiment, the process 2300 can include a step 2304 of determining a midline of the buried object 100 based on where the change in the electromagnetic field is maximum when the apparatus is moved across the longitudinal axis of the buried object 100. In an embodiment, the process 2300 can include a step 2306 of moving the device along the determined midline of the implant 100. In an embodiment, the process 2300 can include a step 2308 of determining an edge of the charge storage device 202 of the implant 100 based on the location of the bimodal peak in the change in the electromagnetic field. In an embodiment, the process 2300 can include an optional step of using an incision marking tool 113 of the device to mark an incision location for removing the implant 100. In an embodiment, the incision location can be at or near the location of the bimodal peak in the change in the electromagnetic field having the greater magnitude. In an embodiment, the process 2300 can include an optional step of removing the implant 100. In an embodiment, removing the implant 100 can include marking an incision at the incision location. In one embodiment, removing the implant 100 can include grasping the charge storage device 202 of the implant 100 (using forceps), which may be stronger than the housing 102 of the implant 100, and pulling the implant 100 out of the body through an incision.

[0102]

[0149] Although the subject matter of the present disclosure has been described and illustrated in some detail with reference to certain exemplary embodiments, including various combinations or subcombinations of features, those skilled in the art will readily recognize other embodiments and variations and modifications thereof that are within the scope of the present disclosure. Furthermore, the description of such embodiments, combinations and subcombinations is not intended to suggest that the claimed subject matter requires features or combinations of features other than those expressly recited in the claims. Accordingly, the scope of the present disclosure is intended to include all modifications and variations that are encompassed within the spirit and scope of the following appended claims.

Claims

1. 1. An apparatus for detecting implants containing magnetic material in a living animal, comprising: a magnetic field generator configured to generate a magnetic field; a sensor configured to detect a change in the magnetic field and to generate a sensor signal indicative of the change in the magnetic field, the magnetic material of the implant causing a change in the magnetic field when the sensor is moved over the implant; and a computer configured to use the sensor signal to detect the location of the implant.

2. 2. The apparatus of claim 1, The apparatus, wherein the magnetic field generator comprises a cylindrical magnet.

3. 3. The apparatus of claim 2, The apparatus, wherein the cylindrical magnet is hollow.

4. 2. The apparatus of claim 1, The apparatus, wherein the magnetic field generator comprises two or more magnets.

5. 5. The apparatus of claim 4, The apparatus, wherein the magnetic field generator further comprises a housing configured to hold the two or more magnets.

6. 6. An apparatus according to claim 4 or 5, comprising: The apparatus, wherein the magnetic field generator comprises four magnets.

7. An apparatus according to any one of claims 4 to 6, 13. The apparatus, wherein the magnetic field generator comprises six magnets.

8. An apparatus according to any one of claims 1 to 7, The apparatus, wherein the magnetic field generator comprises one or more permanent magnets.

9. An apparatus according to any one of claims 1 to 8, The apparatus, wherein the magnetic field generator comprises one or more electromagnets.

10. An apparatus according to any one of claims 1 to 9, The apparatus, wherein the magnetic field generated by the magnetic field generator is a substantially uniform magnetic field.

11. An apparatus according to any one of claims 1 to 10, An apparatus, wherein the magnetic field is substantially symmetric about a longitudinal axis at the center of the field generator.

12. An apparatus according to any one of claims 1 to 9, An apparatus wherein the magnetic field is non-uniform and / or asymmetric with respect to a longitudinal axis at the center of the field generator.

13. 13. An apparatus according to claim 11 or 12, comprising: An apparatus wherein the sensor is positioned along or offset from the longitudinal axis at the center of the magnetic field generator.

14. An apparatus according to any one of claims 1 to 13, comprising: In detecting the location of the implant, the computer is configured to determine an edge of the magnetic material of the implant based on a location of a bimodal peak in the change in the magnetic field during movement of the sensor along the longitudinal axis of the implant.

15. 15. The apparatus of claim 14, The device, wherein the computer is configured to determine an edge of the implant based on the determined edge of the magnetic material of the implant and one or more offsets between the edge of the implant and an edge of the magnetic material of the implant.

16. 16. An apparatus according to claim 14 or 15, comprising: The computer is configured to determine a depth of the implant based on a magnitude of the change in the magnetic field at a bimodal peak in the change in the magnetic field during the movement of the sensor along the longitudinal axis of the implant.

17. An apparatus according to any one of claims 14 to 16, comprising: The computer is configured to determine an orientation of the implant based on a difference between the magnitude of the change in the magnetic field at the bimodal peaks of the change in the magnetic field during the movement of the sensor along the longitudinal axis of the implant.

18. An apparatus according to any one of claims 1 to 17, comprising: The apparatus, wherein the computer is configured to calculate a derivative of the change in the magnetic field and to use the calculated derivative to detect the location of the implant.

19. 20. The apparatus of claim 18, The apparatus, wherein the computer is configured to determine an edge of the magnetic material of the implant based on where the derivative of the change in the magnetic field during movement of the sensor along the longitudinal axis of the implant equals zero.

20. 20. The apparatus of claim 19, The computer is configured to determine a depth of the implant based on a magnitude of the change in the magnetic field at the location where the derivative of the change in the magnetic field during the movement of the sensor along the longitudinal axis of the implant equals zero.

21. 21. Apparatus according to claim 19 or 20, comprising: The computer is configured to determine an orientation of the implant based on a difference between a magnitude of the change in the magnetic field at the location where the derivative of the change in the magnetic field during the movement of the sensor along the longitudinal axis of the implant is equal to zero.

22. An apparatus according to any one of claims 18 to 21, comprising: The apparatus, wherein the computer is configured to determine a midline of the implant based on where the derivative of the change in the magnetic field during movement of the sensor across the longitudinal axis of the implant equals zero.

23. An apparatus according to any one of claims 1 to 22, comprising: The apparatus, wherein the computer is further configured to use the one or more sensor signals to detect an orientation of the implant.

24. An apparatus according to any one of claims 1 to 23, comprising: An apparatus further comprising a display, the computer configured to cause the display to display an indication of the detected location of the implant.

25. 25. The apparatus of claim 24, The apparatus, wherein the display is disposed above the sensor.

26. 26. Apparatus according to claim 24 or 25, comprising: wherein the indication of the detected location of the buried object includes a buried object image, and a location of the buried object image on the screen of the display relative to a point on the screen of the display corresponds to the detected location of the buried object relative to the sensor.

27. 27. The apparatus of claim 26, The implant image has an orientation that corresponds to a detected orientation of the implant.

28. An apparatus according to any one of claims 1 to 27, comprising: The apparatus further includes an incision marking tool configured to identify an incision location for removal of the implant.

29. An apparatus according to any one of claims 1 to 28, comprising: A device wherein the diameter of the magnetic field generator is equal to the length of the implant.

30. An apparatus according to any one of claims 1 to 29, comprising: The apparatus further includes a position detector configured to generate a location signal indicative of a location of the sensor on a skin surface.

31. 31. The apparatus of claim 30, The apparatus, wherein the position detector includes a motion detector configured to detect movement of the sensor and to generate a motion signal indicative of the detected movement of the sensor, and wherein the location signal includes the motion signal.

32. 32. Apparatus according to claim 30 or 31, comprising: The apparatus, wherein the computer is configured to use the sensor signal and the location signal to generate a map of sensor signals at different locations of the sensor on the skin surface.

33. 1. A method for detecting implants containing magnetic material in a living animal, comprising: using a magnetic field generator to generate a magnetic field; using a sensor to detect changes in the magnetic field and to generate a sensor signal indicative of the changes in the magnetic field, the magnetic material of the implant causing a change in the magnetic field when the sensor is moved over the implant; and using a computer to detect a location of the implant based on the sensor signal.

34. 34. The method of claim 33, The method, wherein detecting the location of the implant includes determining an edge of the magnetic material of the implant based on a location of a bimodal peak in the change in the magnetic field during movement of the sensor along the longitudinal axis of the implant.

35. 1. A method for detecting implants containing magnetic material in a living animal, comprising: moving a device including a magnetic field generator and a sensor across a longitudinal axis of the implant, the magnetic material of the implant causing a change in a magnetic field generated by the magnetic field generator as the device is moved across the longitudinal axis of the implant, and the sensor detecting the change in the magnetic field; determining a midline of the implant based on where the change in the magnetic field is greatest as the device is moved across the longitudinal axis of the implant; moving the device along the determined midline of the implant; and determining an edge of the magnetic material of the implant based on a location of a bimodal peak in the change in the magnetic field as the device is moved along the determined midline of the implant.

36. 36. The method of claim 35, The method further includes using an incision marking tool of the apparatus to mark an incision location for removal of the implant.

37. 1. An apparatus for detecting implants in a living animal, the apparatus comprising: an electromagnetic field generator configured to generate an electromagnetic field; a sensor configured to detect a change in the electromagnetic field and to generate a sensor signal indicative of the change in the electromagnetic field, wherein at least the charge storage device of the implant causes a change in the electromagnetic field when the sensor is moved over the implant; and a computer configured to use the sensor signal to detect the location of the implant.

38. 1. A method for detecting an implant containing a charge storage device in a living animal, comprising: using an electromagnetic field generator to generate an electromagnetic field; using a sensor to detect changes in the electromagnetic field and to generate a sensor signal indicative of the changes in the electromagnetic field, wherein at least the charge storage device of the implant causes a change in the electromagnetic field when the sensor is moved over the implant; and using a computer to detect a location of the implant based on the sensor signal.

39. 1. A method for detecting an implant containing a charge storage device in a living animal, comprising: moving an apparatus including an electromagnetic field generator and a sensor across a longitudinal axis of the implant, the charge storage device of the implant causing a change in an electromagnetic field generated by the electromagnetic field generator as the apparatus is moved across the longitudinal axis of the implant, and the sensor detecting the change in the electromagnetic field; determining a midline of the implant based on where the change in the electromagnetic field is greatest as the device is moved across the longitudinal axis of the implant; moving the device along the determined midline of the implant; and determining an edge of the charge storage device of the implant based on a location of a bimodal peak in the change in the electromagnetic field as the apparatus is moved along the determined midline of the implant.

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